[mythtv-users] 2 Problems: No Sound, Can't change channel

[Ian Batterbee]

>
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>Playing raw data '/dev/dsp' : Unsigned 8 bit, Rate 8000 Hz, Mono
>underrun!!! (at least 9.256 ms long)
>underrun!!! (at least 10.637 ms long)
>underrun!!! (at least 10.789 ms long)
>underrun!!! (at least 9.950 ms long)
>

I have what sounds like exactly the same problem with the sound (although I have no problem changing channels).. I tried changing the sampling rate it played them back at, but the default of 8000Hz seems to be the only one that sounds 'right', barring the choppy sound and underruns.

But ignoring the fact that it gets underruns, running aplay does produce some sound, so I worked on the theory that mythtv isn't getting anything from the sound card.

To test that, I ran xawtv at the same time as mythtv was running, and as soon as xawtv started, it must have unmuted the tv card and mythtv started playing the same type of distorted sound that aplay had produced earlier.

Bear in mind that there's a delay caused by the encoding and decoding, but allowing for that, the effect was "immediate".. when I quit xawtv, myth played what was left in the buffer and then went silent again.

To make absolutely sure, I ran myth, went to 'watch tv', then plugged the speakers directly into the tv card, and yup, no sound at all.  In 

So it seems at least one problem is that myth isn't enabling the tv sound on the tv card - something that tvtime and xawtv are both quite happy to do, and I can listen to the TV fine when using either of those apps

The second problem is the buffer underruns.. it may be that the card can only record at specific setting(s), eg exactly 44100, or exactly xxxx, and whatever it is being played back it is not what it was recorded it.. that's just a guess.. I've read some posts about some sound drivers/cards being very picky about it, but I don't think there's any way to tell myth to use specific settings for sampling the sound.

Perhaps someone can shed some light on this problem with this extra information ?

My sound card is an onboard alsa-driven via82xx